Although I've seen no empirical evidence of it, I think my dog has been eating my garbage while I'm out. I haven't switched dog foods and I cannot see any other reason for his unholy intestinal gas of late ... oh, the humanity
... maybe he in the cat are in cahoots and she tidies up the scene of the crime after commision. He seems healthy otherwise, though. Whatever the case, he's going to the vet soon.
P.S. At least he has the common decency to go into the next room and cower shamedly after, and in some fortunate cases, before the fact. That's more than I can say for some people. :/